package zjh_20230316;

public class Demo02 {
    public static void main(String[] args) {
        String s = "abc21b416u";
        int sum = 0;
        for (int i = 0; i < s.length(); i++) {
            if (s.charAt(i) <= 57 && s.charAt(i)  >= 48){
                sum++;
            }
        }
        System.out.println("数字个数为："+ sum);
    }
}
